Abstract

In the Phaedrus‐T tokamak [R. Majeski etal., Phys Fluids B 5, 2506 (1993)], Alfvén waves are indirectly driven by a fast waveantenna array. Small fractions of minority ions can couple Alfvén and ion–ion hybridwaves and have a large effect on the wave numbers accessible for a given launched frequency. A discrete spectrum and toroidal damping for these modes has been identified by measuring dispersionproperties at the edge. Landau damping is predicted to be large and spatially localized and to be responsible for the experimentally observed electron heating (T. Intrator etal., ‘‘Alfvén ion–ion hybridwave heating in the Phaedrus‐T tokamak,’’ to appear in Phys. Plasmas) and current drive near the core of the tokamak plasmas.